The offset collision denotes that in a case where two railcars 31 and 32 are running in directions opposite to each other, one vehicle (hereinafter may be referred to as an “oncoming vehicle”) 31 derails from a track and collides with a part of the other vehicle (hereinafter may be referred to as a “running vehicle”) 32 as shown in FIG. 8. Various countermeasures against the offset collision are being taken in railcars. As one example of the countermeasure against the offset collision, it is effective to configure a side bodyshell by using a double skin structure as in PTLs 1 and 2 to improve the stiffness of the side bodyshell or form an inclined surface at a front end portion of the side bodyshell of each of the vehicles 31 and 32 such that the vehicles 31 and 32 separate from each other at the time of the collision.